Every mother faces impossible choices. Vaccination is one of the hardest. For single mom Kate O'Hara, there was no decision to make. Her daughter, Rosie, is one of a small percentage of children who can't be vaccinated against measles. All Kate can do is hope that her little girl is safe.

Beyond the Titan wall lies the Feral Zone, and the only people who break quarantine and venture there are the "fetches", who are paid exorbitant sums to bring back items that were left behind when the wall went up--but Delaney McEvoy's father is there and she is being forced to find him and bring him back.

Six months after vanishing into an underground silo with sixty others, Wynter and Chase emerge to find the area abandoned. There is no sign of Noah and the rest of the group that was supposed to greet them when they emerged--the same people Wynter was counting on to help her locate the IV antibiotics her gravely ill friend, Julie, needs in order to live. As the clock ticks down on Julie's life, Wynter and Chase embark on a desperate search for medicine...